It is a common practice to connect a cable to a printed circuit board (PCB) by utilizing a plug connector at an end of the cable which is intended for insertion into an opposing mating connector. The mating connector is typically mounted on the PCB placed within a housing of an electronic device. There may be other electronic modules mounted on the PCB. Each electronic module may emit electromagnetic interference (EMI) that can interfere and negatively influence the signals transmission between the connectors.
The mating connector may be shielded from EMI by using a metal shielding cage (sometimes referred to as an EMI shielding cage) that is also mounted on the PCB and which surrounds the mating connector in the electronic device. The cage has an opening which opens to a faceplate. The opening defines an entrance leading towards the mating connector into which the plug connector is inserted. However, even with the use of the cage, EMI may still be present, primarily at the area where the cage meets the PCB and around the opening of the faceplate into which the cage opening extends.
Conductive gaskets of various forms have been developed to address this problem. U.S. Pat. No. 6,878,872 (Lloyd et al.) purportedly discloses an electrically conductive compressible gasket for a shielding cage with multiple module receiving bays. However, gaskets made using conductive foams can be prone to tearing and other damage. Further, the degree of EMI protection may be dependent on the amount of conductive material in the conductive foam.
For the benefit of consumers, standards have been established within the electronics industry, especially in the areas of connector mechanical interfaces, signal and data transmission protocols, and signal and data exchange protocols. This interoperability will allow an electronic module that is made by one vendor to be replaceable with a similar module from another vendor. Thus, consumers will have more product choices and can benefit from this competition with more competitive device pricing.
In the electronics industry, there are many standards committees including, but not limited to, the Institute of Electric and Electronic Engineers (IEEE) Committee which governs the specifications for data communication, the T10 Committee which defines the standards for data storage, and the Small Form Factor (SFF) Committee which specifies the standards for mechanical interfaces for connectors. SFF 8088 is one such standard set by the SFF Committee and it is a specification for mini multi-lane shielded connectors.
For reasons provided earlier, there is motivation for manufacturers to use conductive metallic gaskets instead of conductive foam gaskets for EMI shielding for their electronic devices. U.S. Pat. No. 7,455,554 (Long) purportedly discloses an EMI shroud with bidirectional contact members. At this moment, the use of a conductive metallic gasket would cause the connectors to be SFF 8088 non-compliant.